ShootingTheBull410 Tests Wallboard Penetration

If you had to defend your home by firing a gun, what happens if you miss? What effect would a stray shot have if it missed the bad guy and instead penetrated through a wall? Would the shot pose a threat to a loved one in an adjoining room, or a neighbor in the next apartment or condominium? While the answer is normally an overwhelming “yes” with conventional hollowpoints or FMJ bullets, it seems like people are always looking for ways to minimize the risk. A viewer wrote to me to say . . .

that at the gun store where he works, some of the salesmen have been selling DRT’s frangible ammunition by telling the customers that “this is frangible ammunition, and it absolutely won’t go through a condominium wall.” The viewer was concerned that this wasn’t true, especially because on DRT’s own website they say that their ammo is designed to pass through semi-hard objects such as drywall or plywood, so certainly it’d go through a wall…right?

I know these tests have been conducted before on various types of ammo. TTAG even published a wallboard penetration test a couple of years ago, but most of the tests I’ve seen haven’t gone the extra step of including ballistic gel after the wallboard in order to capture the bullet and be able to assess its potential lethality after getting through walls. Also, most of the tests I’ve seen have used conventional pistol or rifle ammo, but the question my viewer posed was specifically about one of the newer “exotic” ammo types (since DRT is a jacketed frangible round). Accordingly, I thought maybe it was time to test a few different types of ammo that seemed like they might possibly offer some chance of being less lethal after passing through walls. Or not?

In this test I put some different types of ammo to the test. Federal Premium’s Guard Dog is an expanding full-metal-jacket bullet that claims to minimize overpenetration through walls. DRT classifies their ammo as a “penetrating frangible.” Even though DRT says on their website that their ammo will penetrate through sheetrock, it still raises the question of whether a compressed-powder frangible bullet might be a safer choice for minimizing the potential danger through walls. And Liberty Civil Defense ammo is another unusual one. It’s a lightweight fragmenting bullet that normally disperses into many little fragments upon contact with a body — so perhaps it might prove to be less dangerous after going through a wall?

Finally, I also throw in a load of birdshot from a Taurus Judge. Birdshot (especially birdshot from a handgun) makes for a weak personal defense round, but perhaps the tiny pellets will prove to be incapable of penetrating walls.

I constructed a rig to hold four sheets of 1/2″ drywall, basically simulating two interior walls. To assess the potential lethality of the bullets after passing through the drywall, I set up a block of calibrated 10% ordnance gelatin to catch the bullets and measure their residual penetration depth. A bullet that penetrates only a couple of inches of gel may be capable of inflicting a superficial wound, but would be unlikely to cause a serious injury in most cases. However if the bullet retains enough energy to penetrate a good 8″ or more, it should still be considered lethal.

To really push the limits, I chose to use the most underpowered size of handgun I could — a 3″-barrel pocket pistol chambered in 9mm. I figured that if the bullets go through walls from the smallest of common pistols, then they obviously would go through them from a larger gun.

RESULTS: To the surprise of exactly no one, these tests revealed that yes, bullets go through walls. They just do. Whether the round is a conventional hollowpoint, a garden variety full-metal jacket or a more exotic design, they all easily passed through four sheets of 1/2″ drywall and slammed into the gel block with enough residual energy to cause a potentially fatal hit on anyone unlucky enough to be hit by them.

The birdshot from the handgun was much less dangerous. It was stopped completely by the fourth sheet of drywall. Then again, birdshot from a handgun isn’t really considered an effective manstopping round, so it appears that the lesson here is that if you want to avoid the risk of damage to innocents on the other side of a wall, you either have to compromise the power of your firearm, or you really, really have to be careful to make sure to hit the bad guy. If you miss, that missed shot can and will be dangerous. Any bullet that has the power to do enough damage to a bad guy’s body enough to incapacitate him isn’t going to have any trouble zipping right through wallboard.

I think there are no easy answers here. Defending oneself with a firearm means that you’re legally responsible for every projectile that firearm fires whether that’s out in public in a concealed-carry scenario, or in your own home. It makes no difference. The surest way to minimize any potential of harming an innocent is to not fire at all. But if you’re going to fire, the best thing to do is hit your target. If you miss, those missed shots can and will pose a potentially lethal threat to innocents — whether or not there’s an interior wall between you and the other person.

There has been some discussion that perhaps an AR15 would be a more suitable home defense weapon because the small rifle rounds are supposed to break up more easily than a pistol round when passing through wallboard. I can’t say for sure, as I haven’t tested that yet. But what I can say is that if you’re using a handgun to defend your home, you should be absolutely clear on one aspect — if you miss the bad guy, your handgun bullet is going to go straight through whatever wall it hits, and it will be potentially dangerous or even fatal if it were to hit a person on the other side of that wall (or walls). In short, don’t shoot unless you must, and if you must — don’t miss.

46 Responses to ShootingTheBull410 Tests Wallboard Penetration

Is there any way to simulate a floor? Like, shooting up or down stairs, is a miss as serious? Seems like a floor might normally stop a bullet pretty safely, but maybe I’m wrong. My house is 3 stories, and lots of people live in apartments, seems like a good question.

Part of the problem with testing a floor is that the flooring materials are too varied. For walls, unless you are talking an older home, it’s basically drywall and that’s it. For floors you could have hardwood, laminate, engineered wood, tile, carpet, etc.

Most apartment buildings and condos use a substance called gypcrete which is what it sounds like, a combination of gypsum (drywall) and concrete. They usually pour a 1 1/2″ to 2″ thick layer and it’s so thin it’s self leveling. I don’t think it’s as hard as concrete when it sets up but it’s harder than drywall. Add to that a layer of 5/8″ drywall and a sheet of 3/4″ OSB or plywood, and carpet, wood, vinyl or tile. I’m guessing it’s not quite bulletproof, but a lot more of a barrier than the walls.

Most “floors” between the ground floor and an upper floor of a house are a piece of drywall (the ceiling), a piece of plywood (the floor), carpet pad, and some carpet. Plywood is not very hard to penetrate. I’m guessing this layup is fairly comparable to four sheets of drywall.

Stairs are more likely to have some 1x pine boards involved than floors, but not necessarily.

Floors in apartments (or condos) vary tremendously. Some are like houses, others are fairly substantial concrete.

The bottom line is you have to assume a miss indoors is going through whatever wall is behind it or above it, including an exterior wall if you live in a wood frame house with conventional siding.

That is pretty much what I was thinking. I know the support structure of my floors is 2″x12″ but no idea what the floor itself is. It has to be pretty stout to feel solid when you walk, especially if there are a dozen of you in a room. If the actual surface is plywood, it must be at least 5/8, maybe 3/4. So would normal handgun ammo penetrate that?

… “The tests were run in a somewhat ad-hoc manner due to the fact that other people selfishly insisted on using the range at the same time, so it was not always possible to call a cease fire every three shots. This forced us to do shooting and photography by batches, which led to come confusion when sorting through the photos afterward. ”

plus, they did not have ballistic gel after the wallboard.

Testing methodology is everything (especially, consistency). Garbage in, garbage out. That’s why when it comes to ballistic tests, I trust ShootingTheBull410 and very few other people on the interwebs.

My house is old enough that I have Lath and plaster and they are like concrete. I had to do some work at my house to rearrange two smaller rooms into one and it was painful. Not only do you have the Lath and plaster on the facing wall, the way my walls are constructed there was like a concrete like backer board and insulation in the middle.

While I still believe a bullet will go through, wonder how much more it would travel because I believe it would slow down more than the blue boards.

Was able to use a variety of shotguns and loads on a lathe and plaster house scheduled for destruction. Solid core doors also. All gauges and all loads, buckshot and birdshot penetrated. At house ranges even the bird shot loads hit pretty much as a solid mass. If you had been standing on the other side of the walls or doors you would have had a bad day.

All the guns used were standard length hunting guns. In the old days we weren’t too tacticool.

This is excellent testing. I’ve seen firsthand how even weak handgun rounds penetrate interior components of houses. It’s eye-opening.

For future testing, I would really like to see:

1. Testing on penetration of common exterior wall materials. I suspect that a miss could exit one house and enter another while still retaining dangerous velocities if the houses are wood frame with conventional siding and close together.
2. Testing penetration of building materials with some .223 rounds. I’m skeptical of the claims that .223 rounds break up.

Another enlightening exercise is to calculate how far handgun rounds will travel when fired from eye height on a level trajectory. It can easily be 200 yards. This gets back to why I’d like to see testing on exterior wall materials.

Kind of makes you rethink the idea of a shotgun with birdshot being ‘apartment safe’. If that little judge isn’t an 18+” barreled 12ga. wouldn’t be by a long shot.

I would have liked to see something like a 4″ barreled 9mm with Gold Dots as a control. Another interesting thing would be to fire the rounds through 10″ or so of ballistics gel and into the walls to see what would happen if you hit your target, how dangerous is the over penetrating bullet?

I live in an old brick house with 8 fireplaces and even the inside walls are of brick made up of raised panel pine about 3/4 of an inch a layer of brick a cavity about 2″ deep another brick and panel of chestnut wood in 2 of the rooms so about 10 inches of rather hard stuff
Ant one of the fireplaces is so huge I could burn 7 foot logs in it and it was set up for cooking in the 1700s

the house was built by a local brick maker and shipyard owner and is full of heavy hardwood timbers as well. The central chimney mass is about 25′ by 30′ and the solid brick staircase goes up through the middle of it…. I have few shoot through worries here

the outside walls are 2 briks thick a cavity another 2 briks thick and the inside 1 inch thick wood panels both pine and chestnut depending on the use of the room floors are 8×12 summer beams of chestnut and oak subfloor 1 1/2″ thick various hardwood and then a surface of again thick hardwood of different sorts mostly chestnut and oak now refinished down to a bit over an inch thick ceiling is hand split lath and lime with horsehair plaster total about an inch where I have cut through it for wiring etc. I have a 50 foot range in my basement and on the top floor a .45 colt shot down there sounds like a cap gun going off
The point of all this is that there are lots of different kinds of houses. I have a friend in Vermont with a stone house that I think would stand up to light artillery

I had an unfortunate incident where I accidently discharged my .380 LCP. The self protection round went through both sides of the drywall, including a portion of a 2 x 4 stud, exiting the other side it penetrated both sides of a workbench steel corner, and scrapped the garage concrete floor where it came to rest. So even the lowly claimed .380 has more power than most people realize.

Using a shorter barrel 9mm might have dropped the frangible and fragmenting rounds below their velocity thresholds, much the way a short barrel on a 5.56 drops velocity below fragmenting in gel or a body.

I would REALLY like to see a 12 gauge video from him. I haven’t found any other ballistics YouTubers whose videos are as professionally done and scientific. Who uses a .410 Judge for home defense as opposed to an 870/500?

Been thinking of getting one, except the dealer tells me they have a lot of “return for repair”, anyway, the judge would be a lot easier and quicker to handle if you were in bed, which is where most folks would be in the wee hours of the morning.

With my luck, if I lived in a log house, and fired a shot and missed and the bullet hit the exterior log wall, it would probably go exactly in between where two logs come together, and pass right through the relatively thin caulking, and a couple inches of wood.

So many variables. Where I work houses and many smaller apartments are plaster and lath. The high rises are all compartmentalized ,that is concrete units .

Where I live sure sheet rock. However toss in some insulation half a dozen coats of paint on each side,studs,pipes.wires,paintings ,pictures on the walls and oh ya furniture ,now you have a realistic test. Oh and to exit a house plywood and ceder shakes in my case.

That said,yes there is risk firing through walls. I’ve just never seen a proper test yet.

There is fundamentally a conflicting requirement here. Any round with acceptable terminal ballistics on a human is going to penetrate drywall and retain a bunch of energy on the other side. Unless home construction changes dramatically or something about the laws of physics changes, that’s just the way it is.

In the meantime, “don’t shoot unless you must, and if you must — don’t miss” remains sound advice. It’s also worthwhile to walk your home and think about where people sleep and what shots you will/won’t take in a HD scenario, since not missing is easier said than done.

I know a lot of folks use FMJ in a small caliber like 380,32 or 22. It seems like if the lowly FMJ 380 could start WW1 maybe it ain’t so bad. Personally I rely on 12guage 00buck for home defense. But I don’t live in an apartment. I also have mostly solid brick to shoot through…